(1) Field of the Invention
The present invention relates to an e-mail transmission/reception system. More specifically, the present invention relates to a system for the transmission/reception of e-mail with attached files.
(2) Description of the Related Art
The Internet is basically available through terminals provided at offices and homes. Recently, however, new usage patterns of the Internet such as “mobile computing” and “mobile Internet” are becoming common. In the mobile computing, the Internet is accessed by cellular phones and Personal Handyphone Systems (PHS) connected to personal computers or Personal Digital Assistants (PDA). The mobile Internet (e.g., Internet service for cellular phones) refers to a usage pattern that combines mobile machines, which are free from restrictions on time and space, and the Internet, which contains information from all over the world. As the mobile computing and the mobile Internet become widespread, we become able to easily send and receive e-mail at anytime and anyplace. However, when sending e-mail with attached files to cellular phones and PHSs, the attached files are automatically deleted in most of the mobile Internet services.
Meanwhile, there are some mobile Internet services for storing attached files in the server and forwarding them to another receiver's address. For instance, a service named “MOZIO e-mail” provided by ASTEL group including TOKYO TELECOMMUNICATION NETWORK CO., INC, stores an attached file included in the received e-mail in a mail server, and adds a message of “The mail includes an attached file” to the e-mail from which the attached file has been removed so as to inform a subscriber of the existence of the attached file. Then, if the subscriber forwards the e-mail with such a message from the PHS to another address that is available from a personal computer or the like, the mail server attaches the stored file to the e-mail and sends the e-mail to the other address. Thus, the subscriber can receive the e-mail with the attached file by means of the personal computer.
In addition, a similar technology is disclosed in the Japanese Laid-Open Patent Application No. 11-175419. This application discloses an e-mail transmission/reception system in which, when forwarding an e-mail with an attached file from a mail terminal to another receiver's address, there is no necessity to transmit the attached file from the mail terminal to a mail server.
This e-mail transmission/reception system is composed of a mail terminal which is equipped with Mail User Agent (MUA), a mail gateway that relays e-mail between the mail terminal and a mail server, and the mail server which is equipped with Mail Transport Agent (MTA).
Here, the MUA is a program for providing a user interface to read and write e-mail, and the MTA is a program for delivering e-mail.
When receiving an acquisition request for the e-mail, which is received by the mail server, from the mail terminal, the mail gateway acquires the e-mail from the mail server, separates an attached file from the e-mail, stores the separated file having a mail ID, and manages the file. When receiving e-mail (consisting of the main body and a mail ID for identifying the original mail) that should be forwarded to another address from the mail terminal, the mail gateway attaches the stored and managed attached file to the e-mail on the basis of the mail ID for identifying the original mail and sends the e-mail consisting of the main body and the attached file to the mail server.
In this way, the above-mentioned system enables the mail terminal to send e-mail with an attached file to a forwarding address only by sending e-mail having a mail ID for identifying the original mail to the mail gateway.
However, according to the above-mentioned conventional system, when a plurality of attached files are included in the mail, there is a problem in that a file to be attached cannot be selected from the plurality of attached files but all files included in the e-mail are unconditionally attached to the e-mail, because mail IDs are used for linking e-mail and attached files. That is, in the conventional system, it is impossible to send e-mail including an attached file that a user selects from among a plurality of attached files without attaching the attached file by the mail terminal. The same goes for the above-mentioned service “MOZIO e-mail.”